Family Hainesiidae Tiele, 1929

Hainesiinae, Tiele, 1929: 103.

Tope genus: Hainesia L. Pfeiffer, 1856. Remarks: Tere is one available family-group name for Madagascan Cyclophoroidea: Hainesiinae Tiele, 1929, which was treated as a synonym of the subfamily Megalomastomatinae (family Megalomastomatidae) by Bouchet et al. (2017), based on the phylogeny of Webster et al. (2012). However, the later publication has not included any species from the Caribbean Islands, where Megalomastoma Swainson, 1840, the type species of Megalomastomatidae lives, but only two species of Acroptochia from Madagascar. In the absence of molecular information, the evolutionary relationship of the Caribbean Megalomastomatidae and the Madagascan Hainesia and Acroptochia is unknown. Nevertheless, it is not likely that they would belong to the same monophyletic group. Terefore, we suggest using Hainesiidae for Hainesiinae (including Hainesia and Acroptochia) and Boucardicinae. Egorov (2009) treated Hainesiidae as a family in its own right and included the genera Acroptochia, Hainesia, and, with doubt, Anosocolus and Boucardicus. Based on the characters of the radula and operculum, he included Hainesiidae provisionally in Litorinoidei (= Litorinoidea Children, 1834); however, molecular phylogenetic data (Webster et al. 2012) later confirmed that Acroptochia (and therefore, Hainesiidae) belongs to the Cyclophoroidea.

Tere are two additional high-spired operculate genera from Mauritius that might be of relevance to the Madagascan genera in question: Madgeaconcha O. L. Griffiths & Florens, 2004 and Naggsiaconcha O. L. Griffiths & Florens, 2004, but they are much smaller than Acroptochia and Hainesia, and their systematic relationships are highly questionable (Griffiths and Florens 2004). Madgeaconcha, with its minute shell being only slightly larger than 1 mm, is similar to Acmella W. T Blandford, 1869 in size and shape (see Vermeulen et al. 2015, Das et al. 2021), and therefore, it probably belongs to the family Assimineidae. Although Naggsiaconcha is much higher spired than any other terrestrial assimineids, it might also belong to the same family.

Te genera Ankoravaratra Emberton, 2002 (described by Emberton 2002c; type species: Ankoravaratra ambrensis Emberton, 2002, by original designation) and Owengriffithsius Emberton, 2002 (described by Emberton 2002b; type species: Owengriffithsius capdambrae Emberton, 2002, by original designation), also endemic to Madagascar, are currently classified in the families Maizaniidae and Cyclophoridae, respectively. Nevertheless, their systematic position is highly questionable, and it is possible that they would also belong to the Hainesiidae.